The formula is the same: Boy meets girl, boy loses girl, boy gets girl back. Only in the case of bromance movies like the Paul Rudd/Jason Segel pairing I Love You, Man , it's two straight men competing for each other's affections.

"Romantic comedies often share the same basic construct," states the press notes for one such popcorn flick, out this Friday. "Boy meets girl, boy loses girl, boy gets girl back."

The only difference is that this film is about two boys. Well, two men. Two straight men, Peter (Paul Rudd) and Sydney (Jason Segel), whose blossoming friendship does indeed follow the contours of a Hollywood romance and, after various challenges and derailments, is finally cemented at a wedding. The picture's release arguably inaugurates a new genre, or at least sees a long-closeted subgenre finally daring to speak its name. With I Love You, Man -- tag line: "Are you man enough to say it?" -- the bromance is finally out and proud.

Homosociability has been a key component of American cinema from its earliest days, infusing D.W. Griffith's formally trailblazing (and politically obnoxious) The Birth of a Nation and underpinning such bedrock genres as gangster pictures, westerns, and war movies. Film history is littered with palling around of the kind enjoyed by Humphrey Bogart and Claude Rains in Casablanca , or James Dean and Sal Mineo in Rebel Without A Cause . The Odd Couple , which reached theaters in 1968, could be seen as a boy-boy twist on the opposites-attract romantic comedy.

But if we take the bromance to be a picture in which an intense, devoted male friendship is at the core of the story and action, then 1969 was year zero. That year, mainstream audiences were treated to not one but two such pictures: both Butch Cassidy & the Sundance Kid and Midnight Cowboy focused on ostensibly platonic partnerships that endured -- unlike those pictures' boy-girl matches -- for richer and poorer, in sickness and in health, till death did they part. Stetsons and man-love would not be so closely aligned again until Brokeback Mountain .

In the '80s, the male-relationship picture took center stage via the buddy movie. The likes of Midnight Run , Running Scared , and, of course, the Lethal Weapon cycle were all constructed around odd couples whose death-defying, seat-of-the-pants brushes with explosive violence only partly obscured the affection and even emotional vulnerability on which their partnerships were based.

By the '90s, such twosomes were edging out of the closet -- if not in terms of sexual identity then in the sense that generic or contingent excuses for such intimacy were no longer considered vitally important. On-screen, the bond between Joey and Chandler was by some way the most convincing pairing of the whole run of Friends , while off-screen the Matt Damon-Ben Affleck double-act opened the door to a kind of overtly expressed emotionality that would have been anathema to earlier boys' clubs such as Sinatra's Rat Pack. A straight line -- no pun intended -- can be drawn from their joint media persona to the coverage of Lance Armstrong's cycling idyll with Matthew McConaughey and Jake Gyllenhaal. Meanwhile, the bromance has steadily become arguably the dominant strain of mainstream comedy, and secured footholds across the cultural spectrum, from video games to novels .

Traditionally, bromantic movies have deployed a degree of low-level homophobia in a plain attempt to deflect the notion that such intimacy might be, you know, kinda faggy. Midnight Cowboy , directed by the gay filmmaker John Schlesinger, pitched Jon Voight and Dustin Hoffman's relationship in opposition to an array of unsympathetic homosexual characters. This tendency continued through the buddy-movie era, to find its peak in the grotesque gay panic of 2007's I Now Pronounce You Chuck and Larry , and was arguably evident in MTV's reality show Bromance , in which, having constructively ejected the only openly gay contestant in the first episode, the others felt free to get up close and personal without worrying too much aboutâ€¦you know.

Yet over the past few years other strands of the bromance genre have been nudging closer to overtly acknowledged homoeroticism. Much of this can be ascribed to movies directed or produced by Judd Apatow: The 40-Year-Old Virgin 's fresh take on emotional openness in male friendships, for instance, was followed by Seth Rogen and Paul Rudd's quasi-romantic Las Vegas getaway in Knocked Up . In Superbad , male friendship was not only privileged and romanticized -- "I wanna go to the rooftops and scream, 'I love my best friend Evan!'" Jonah Hill gushes -- but paired with a stream of lovingly crafted doodles of, well, doodles: a delirious barrage of comedic cocks presented in blatant defiance of jibes about masculinity.

Similarly, the buddies in last year's Pineapple Express talked not only about buying each other heart necklaces but about sucking each other off. The line "I wanna be inside you, homes" might have been funny, but it was also a sincere expression of affection. On the minus side, the film also has a flaming scapegoat character -- two steps forward, one mince back, perhaps.

I Love You, Man takes this tolerant tendency to new heights. In the picture, nebbish real estate broker Peter (Rudd) realizes he has no male friends close enough to serve as his best man, so he embarks on a series of "man-dates" that lead to his connection with free-wheeling Sydney (Segel). Bonding over their use of pet names and fondness for Rush (the rock group, not the brand of poppers), the couple connect against a queer backdrop which, unlike that of, say, I Now Pronounce You Chuck and Larry , works in concert with rather than counterpoint to their bond.

As well as sympathetically coding Peter as non-macho -- he can't play poker, gets on with the office girls, fights by slapping -- the movie offers the hyper-macho but equally sympathetic presence of Lou Ferrigno, as one of Peter's clients, and an amusingly WASPish gay architect whom Peter inadvertently leads on.

Most intriguing, however, is Peter's brother, Robbie (Andy Samberg), who is both openly gay and a role model of masculinity. A man's man without being macho, he's a personal trainer who only has sex with straight guys and is the apple of their gruff father's eye, but is also unimpeachably friendly and supportive, and Peter's main source of advice and encouragement. Sure, you could read Robbie as an assimilationist's wet dream, an implicit rejection of effeminacy and otherness, but to me, the character played more like a case study in unruffled post-homophobia. And this is where the true value of the bromance form lies -- not only in its fostering of the notion that emotional expressiveness between men is a valuable thing, but in its growing acknowledgment that the association of this expressiveness with the gay experience can be something not to defy but to embrace.

Another reality TV show, The Principal's Office , recently featured two ostensibly straight high school seniors dirty dancing with one another for comic effect. The butt of their joke was not gayness but the prudery of their principal, and they were happy to bump, grind, and hold hands without seeming to fear for their schoolyard credibility. Whether Midnight Cowboy , Lethal Weapon, or Pineapple Express hold a special place in their hearts is tough to say, but it's hard to watch their antics without feeling a warm, bromantic glow.